1 /*- 2 * Copyright (c) 2001 Dag-Erling Co�dan Sm�rgrav 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #include <sys/param.h> 32 #include <sys/kernel.h> 33 #include <sys/systm.h> 34 #include <sys/lock.h> 35 #include <sys/malloc.h> 36 #include <sys/module.h> 37 #include <sys/mount.h> 38 #include <sys/mutex.h> 39 #include <sys/proc.h> 40 #include <sys/sbuf.h> 41 #include <sys/sysctl.h> 42 #include <sys/vnode.h> 43 44 #include <fs/pseudofs/pseudofs.h> 45 #include <fs/pseudofs/pseudofs_internal.h> 46 47 static MALLOC_DEFINE(M_PFSNODES, "pfs_nodes", "pseudofs nodes"); 48 49 SYSCTL_NODE(_vfs, OID_AUTO, pfs, CTLFLAG_RW, 0, 50 "pseudofs"); 51 52 #if PFS_FSNAMELEN != MFSNAMELEN 53 #error "PFS_FSNAMELEN is not equal to MFSNAMELEN" 54 #endif 55 56 /* 57 * Add a node to a directory 58 */ 59 static int 60 _pfs_add_node(struct pfs_node *parent, struct pfs_node *node) 61 { 62 KASSERT(parent != NULL, 63 ("%s(): parent is NULL", __func__)); 64 KASSERT(parent->pn_info != NULL, 65 ("%s(): parent has no pn_info", __func__)); 66 KASSERT(parent->pn_type == pfstype_dir || 67 parent->pn_type == pfstype_procdir || 68 parent->pn_type == pfstype_root, 69 ("%s(): parent is not a directory", __func__)); 70 71 /* XXX should check for duplicate names etc. */ 72 73 mtx_lock(&parent->pn_info->pi_mutex); 74 node->pn_info = parent->pn_info; 75 node->pn_parent = parent; 76 node->pn_next = parent->pn_nodes; 77 parent->pn_nodes = node; 78 /* Propagate flag to all child nodes (and thus their vnodes) */ 79 if ((parent->pn_flags & PFS_PROCDEP) != 0) 80 node->pn_flags |= PFS_PROCDEP; 81 mtx_unlock(&parent->pn_info->pi_mutex); 82 83 return (0); 84 } 85 86 /* 87 * Add . and .. to a directory 88 */ 89 static int 90 _pfs_fixup_dir(struct pfs_node *parent) 91 { 92 struct pfs_node *dir; 93 94 MALLOC(dir, struct pfs_node *, sizeof *dir, 95 M_PFSNODES, M_ZERO); 96 dir->pn_name[0] = '.'; 97 dir->pn_type = pfstype_this; 98 99 if (_pfs_add_node(parent, dir) != 0) { 100 FREE(dir, M_PFSNODES); 101 return (-1); 102 } 103 104 MALLOC(dir, struct pfs_node *, sizeof *dir, 105 M_PFSNODES, M_ZERO); 106 dir->pn_name[0] = dir->pn_name[1] = '.'; 107 dir->pn_type = pfstype_parent; 108 109 if (_pfs_add_node(parent, dir) != 0) { 110 FREE(dir, M_PFSNODES); 111 return (-1); 112 } 113 114 return (0); 115 } 116 117 /* 118 * Create a directory 119 */ 120 struct pfs_node * 121 pfs_create_dir(struct pfs_node *parent, char *name, 122 pfs_attr_t attr, pfs_vis_t vis, int flags) 123 { 124 struct pfs_node *dir; 125 126 KASSERT(strlen(name) < PFS_NAMELEN, 127 ("%s(): node name is too long", __func__)); 128 129 MALLOC(dir, struct pfs_node *, sizeof *dir, 130 M_PFSNODES, M_ZERO); 131 strcpy(dir->pn_name, name); 132 dir->pn_type = (flags & PFS_PROCDEP) ? pfstype_procdir : pfstype_dir; 133 dir->pn_attr = attr; 134 dir->pn_vis = vis; 135 dir->pn_flags = flags; 136 137 if (_pfs_add_node(parent, dir) != 0) { 138 FREE(dir, M_PFSNODES); 139 return (NULL); 140 } 141 142 if (_pfs_fixup_dir(dir) != 0) { 143 pfs_destroy(dir); 144 return (NULL); 145 } 146 147 return (dir); 148 } 149 150 /* 151 * Create a file 152 */ 153 struct pfs_node * 154 pfs_create_file(struct pfs_node *parent, char *name, pfs_fill_t fill, 155 pfs_attr_t attr, pfs_vis_t vis, int flags) 156 { 157 struct pfs_node *node; 158 159 KASSERT(strlen(name) < PFS_NAMELEN, 160 ("%s(): node name is too long", __func__)); 161 162 MALLOC(node, struct pfs_node *, sizeof *node, 163 M_PFSNODES, M_ZERO); 164 strcpy(node->pn_name, name); 165 node->pn_type = pfstype_file; 166 node->pn_func = fill; 167 node->pn_attr = attr; 168 node->pn_vis = vis; 169 node->pn_flags = flags; 170 171 if (_pfs_add_node(parent, node) != 0) { 172 FREE(node, M_PFSNODES); 173 return (NULL); 174 } 175 176 return (node); 177 } 178 179 /* 180 * Create a symlink 181 */ 182 struct pfs_node * 183 pfs_create_link(struct pfs_node *parent, char *name, pfs_fill_t fill, 184 pfs_attr_t attr, pfs_vis_t vis, int flags) 185 { 186 struct pfs_node *node; 187 188 node = pfs_create_file(parent, name, fill, attr, vis, flags); 189 if (node == NULL) 190 return (NULL); 191 node->pn_type = pfstype_symlink; 192 return (node); 193 } 194 195 /* 196 * Destroy a node or a tree of nodes 197 */ 198 int 199 pfs_destroy(struct pfs_node *node) 200 { 201 struct pfs_node *parent, *rover; 202 203 KASSERT(node != NULL, 204 ("%s(): node is NULL", __func__)); 205 KASSERT(node->pn_info != NULL, 206 ("%s(): node has no pn_info", __func__)); 207 208 /* destroy children */ 209 if (node->pn_type == pfstype_dir || 210 node->pn_type == pfstype_procdir || 211 node->pn_type == pfstype_root) 212 while (node->pn_nodes != NULL) 213 pfs_destroy(node->pn_nodes); 214 215 /* unlink from parent */ 216 if ((parent = node->pn_parent) != NULL) { 217 KASSERT(parent->pn_info == node->pn_info, 218 ("%s(): parent has different pn_info", __func__)); 219 mtx_lock(&node->pn_info->pi_mutex); 220 if (parent->pn_nodes == node) { 221 parent->pn_nodes = node->pn_next; 222 } else { 223 rover = parent->pn_nodes; 224 while (rover->pn_next != NULL) { 225 if (rover->pn_next == node) { 226 rover->pn_next = node->pn_next; 227 break; 228 } 229 rover = rover->pn_next; 230 } 231 } 232 mtx_unlock(&node->pn_info->pi_mutex); 233 } 234 235 /* revoke vnodes and release memory */ 236 pfs_disable(node); 237 FREE(node, M_PFSNODES); 238 239 return (0); 240 } 241 242 /* 243 * Mount a pseudofs instance 244 */ 245 int 246 pfs_mount(struct pfs_info *pi, struct mount *mp, struct nameidata *ndp, 247 struct thread *td) 248 { 249 struct statfs *sbp; 250 251 if (mp->mnt_flag & MNT_UPDATE) 252 return (EOPNOTSUPP); 253 254 mp->mnt_flag |= MNT_LOCAL; 255 mp->mnt_data = (qaddr_t)pi; 256 vfs_getnewfsid(mp); 257 258 sbp = &mp->mnt_stat; 259 bcopy(pi->pi_name, sbp->f_mntfromname, sizeof pi->pi_name); 260 sbp->f_bsize = PAGE_SIZE; 261 sbp->f_iosize = PAGE_SIZE; 262 sbp->f_blocks = 1; 263 sbp->f_bfree = 0; 264 sbp->f_bavail = 0; 265 sbp->f_files = 1; 266 sbp->f_ffree = 0; 267 268 return (0); 269 } 270 271 /* 272 * Unmount a pseudofs instance 273 */ 274 int 275 pfs_unmount(struct mount *mp, int mntflags, struct thread *td) 276 { 277 struct pfs_info *pi; 278 int error; 279 280 pi = (struct pfs_info *)mp->mnt_data; 281 282 /* XXX do stuff with pi... */ 283 284 error = vflush(mp, 0, (mntflags & MNT_FORCE) ? FORCECLOSE : 0); 285 return (error); 286 } 287 288 /* 289 * Return a root vnode 290 */ 291 int 292 pfs_root(struct mount *mp, struct vnode **vpp) 293 { 294 struct pfs_info *pi; 295 296 pi = (struct pfs_info *)mp->mnt_data; 297 return pfs_vncache_alloc(mp, vpp, pi->pi_root, NO_PID); 298 } 299 300 /* 301 * Return filesystem stats 302 */ 303 int 304 pfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 305 { 306 bcopy(&mp->mnt_stat, sbp, sizeof *sbp); 307 return (0); 308 } 309 310 /* 311 * Initialize a pseudofs instance 312 */ 313 int 314 pfs_init(struct pfs_info *pi, struct vfsconf *vfc) 315 { 316 struct pfs_node *root; 317 int error; 318 319 mtx_init(&pi->pi_mutex, "pseudofs", NULL, MTX_DEF); 320 321 /* set up the root diretory */ 322 MALLOC(root, struct pfs_node *, sizeof *root, 323 M_PFSNODES, M_ZERO); 324 root->pn_type = pfstype_root; 325 root->pn_name[0] = '/'; 326 root->pn_info = pi; 327 if (_pfs_fixup_dir(root) != 0) { 328 FREE(root, M_PFSNODES); 329 return (ENODEV); /* XXX not really the right errno */ 330 } 331 pi->pi_root = root; 332 333 /* construct file hierarchy */ 334 error = (pi->pi_init)(pi, vfc); 335 if (error) { 336 pfs_destroy(root); 337 pi->pi_root = NULL; 338 mtx_destroy(&pi->pi_mutex); 339 return (error); 340 } 341 342 pfs_fileno_init(pi); 343 if (bootverbose) 344 printf("%s registered\n", pi->pi_name); 345 return (0); 346 } 347 348 /* 349 * Destroy a pseudofs instance 350 */ 351 int 352 pfs_uninit(struct pfs_info *pi, struct vfsconf *vfc) 353 { 354 int error; 355 356 pfs_fileno_uninit(pi); 357 pfs_destroy(pi->pi_root); 358 pi->pi_root = NULL; 359 mtx_destroy(&pi->pi_mutex); 360 if (bootverbose) 361 printf("%s unregistered\n", pi->pi_name); 362 error = (pi->pi_uninit)(pi, vfc); 363 return (error); 364 } 365 366 /* 367 * Handle load / unload events 368 */ 369 static int 370 pfs_modevent(module_t mod, int evt, void *arg) 371 { 372 switch (evt) { 373 case MOD_LOAD: 374 pfs_fileno_load(); 375 pfs_vncache_load(); 376 break; 377 case MOD_UNLOAD: 378 case MOD_SHUTDOWN: 379 pfs_vncache_unload(); 380 pfs_fileno_unload(); 381 break; 382 default: 383 printf("pseudofs: unexpected event type %d\n", evt); 384 break; 385 } 386 return 0; 387 } 388 389 /* 390 * Module declaration 391 */ 392 static moduledata_t pseudofs_data = { 393 "pseudofs", 394 pfs_modevent, 395 NULL 396 }; 397 DECLARE_MODULE(pseudofs, pseudofs_data, SI_SUB_EXEC, SI_ORDER_FIRST); 398 MODULE_VERSION(pseudofs, 1); 399